Cooling Storage Cabinet and Method of Operating Thereof

ABSTRACT

When an internal temperature of a freezing compartment becomes lower than a lower limit temperature T F(OFF)  during R-compartment F-compartment alternate cooling, a request for start of R-individual overcool preventing control is made. Then, the rotational speed of the compressor is decreased by one stage and, subsequently, a three-way valve comes to a “R-side open state”, and thus individual cooling of the refrigerating compartment is executed. Thereafter, after a set time, the rotational speed of the compressor is decreased by one stages. When the refrigerating compartment becomes lower than a lower limit temperature T R(OFF) , a request for stop of the R-individual overcool preventing control is made. Then, the process shifts to individual cooling of the freezing compartment and then, after waiting for the freezing compartment to again become lower than the lower limit temperature, the compressor is stopped. When shifted to the individual cooling of the refrigerating compartment, the rotational speed of the compressor is drastically decreased in a short time, i.e. the cooling capacity is drastically decreased.

TECHNICAL FIELD

The present invention is related to a cooling storage cabinet having aplurality of evaporators and supplying refrigerant from a singlecompressor to the evaporators, and a method of operating the same.

BACKGROUND ART

A known cooling storage cabinet is described in Patent Document 1. Inthis art, a freezing compartment and a refrigerating compartment areformed by separating the inside of a heat-insulating storage cabinetbody. The freezing compartment and the refrigerating compartment eachare heat insulated. The freezing compartment and the refrigeratingcompartment each have respective set temperatures differing from eachother. Each of the compartments has an evaporator, and a singlecompressor supplies refrigerant alternately to evaporators to cool thecompartments.

More specifically, a cooling cycle is configured as follows. An invertermotor operates a compressor. An outlet side of the compressor isconnected to a condenser. The downstream side of the condenser isbranched in two refrigerant supply paths through a three-way valve. Acapillary tube and one of the evaporators are installed in each of therefrigerant supply paths. Outlets of the evaporators each have a commonconnection and have a supply path back to the compressor. Duringoperation of the compressor, refrigerant is supplied alternately to thetwo evaporators by switch of the three-way valve, whereby the freezingcompartment and the refrigerating compartment are alternately cooled. Ina case where the internal temperature of either one of the freezingcompartment and the refrigerating compartment is lower than the settemperature, the other compartment is individually cooled. In a casewhere the internal temperatures of both of the freezing compartment andthe refrigerating compartment are lower than the set temperatures, thecompressor is stopped.

On the other hand, in the case where the compressor is operated by theinverter motor, it is proposed in some arts to cool each of thecompartments along a predetermined temperature curve. For example, atarget temperature curve is stored in advance, and then rotational speedof the compressor is controlled in response to a deviation between atarget temperature and an actual internal temperature, and thereby thecompartment is maintained at the target temperature. With this controlmethod, a continuous ON time of the compressor can be longer. In otherwords, the number of switching between ON and OFF is significantlydecreased. Thus, higher performance and energy consumption can berealized.

[Patent Document 1] Japanese Unexamined Patent Application PublicationNo. 2001-133113

Meanwhile, in the case of performing the control of the compressor asabove, when cooling load is higher because of a circumstance such as ahigher ambient temperature, the rotational speed of the compressor tendsto be controlled at a higher speed. When the alternate cooling of thefreezing compartment and the refrigerating compartment as shown in FIG.12 is performed under such conditions and when the internal temperatureof the freezing compartment becomes lower than the set temperature i.e.a temperature T_(F(off)), the individual cooling of the refrigeratingcompartment is started. However, because of such a higher rotationalspeed of the compressor, there is a concern of over cooling capacity,which results in over cooling of the refrigerating compartment.

Here, in line with conditions of actual use, supposing a case wherestored objects are placed on net racks 2 in the refrigeratingcompartment 1, faces of the net racks 2 are covered with plates 3 asshown in FIG. 13. Then, the temperature (a temperature curve y shown bydashed line in FIG. 12) at a point 5 above an uppermost net rack 2,which is in front of a cold air outlet from an internal fan 4, is ratherlower than the temperature (a temperature curve x shown by solid line inthe same figure) in the vicinity of an internal air inlet, where aR-compartment temperature sensor 6 is positioned. Admittedly, when thetemperature detected by the R-compartment temperature sensor 6 becomeslower than the set temperature, i.e. reaches a temperature T_(R(off)),the cold air stops blowing out. However, until that moment, thedifference in temperature distribution may cause an over-cooled localzone such as the zone on the uppermost net rack 2. This is a problem.

The present invention was completed based on the circumstances as above,and it purpose is to prevent overcooling of the storage compartment inthe case of switching from the alternate cooling of the plurality ofstorage compartments having different set temperatures to the individualcooling of the storage compartment having higher set temperature.

SUMMARY OF THE INVENTION

A method of operating a cooling storage cabinet in accordance with thepresent invention includes providing an inverter compressor, acondenser, a valve unit, a first and a second evaporators, constrictionunits configured to constrict refrigerant flowing into each of theevaporators, and a first and a second storage compartments, the firstand the second storage compartments having respective set temperaturesdiffering from each other, the first and the second storage compartmentshaving the first and the second evaporators; supplying the refrigerantby the valve unit alternately to the evaporators, while changing arotational speed of the inverter compressor based on deviations betweenthe set temperatures of each storage compartment and internaltemperatures of the same storage compartments, thereby alternatelycooling each storage compartment so that the each of the compartmentsbecomes closer to the set temperature; in a case where the internaltemperature of either one of the first and the second storagecompartments is lower than the set temperature, performing individualcooling of only the other storage compartment, and in a case where theinternal temperatures of both of the storage compartments are lower thanthe respective set temperatures, stopping the inverter compressor; andin a case of alternately cooling the first and the second storagecompartments with operation of the inverter compressor and, thereafter,switching to the individual cooling of one of the storage compartmentshaving a higher set temperature, decreasing the rotational speed of theinverter compressor.

The cooling storage cabinet includes a freezing cycle, including aninverter compressor configured to have a changeable rotational speed, acondenser configured to dissipate heat from refrigerant compressed bythe inverter compressor, a valve unit having an inlet and two outlets,the inlet being connected to the condenser side, the two outlets beingconnected to a first and a second refrigerant supply paths, the valveunit being configured to perform flow path switching operation tocommunicatively connect the inlet side thereof selectively with one ofthe first and the second refrigerant supply paths, a first and a secondevaporators, each of the first and the second evaporators beingconfigured to be provided in respective one of the first and the secondrefrigerant supply paths, constriction units, each of the constrictionunits being configured to constrict refrigerant flowing into one of theevaporators, and a refrigerant circulation path configured to provide acommon connection between refrigerant outlet sides of the first and thesecond evaporators, the refrigerant circulation path being configured tobe connected to an refrigerant inlet side of the inverter compressor; astorage cabinet body having a first and a second storage compartments,the first and the second storage compartments being configured to haveset temperatures differing from each other and to be cooled by cold airgenerated by the first and the second evaporators; a first and a secondtemperature sensors, each of the first and the second temperaturesensors being configured to detect internal temperature of respectiveone of the first and the second storage compartments; and an operationcontrol means for, during operation of the inverter compressor,supplying the refrigerant by the valve unit alternately to theevaporators, while changing a rotational speed of the invertercompressor based on deviations between the set temperatures of thestorage compartments each and internal temperatures of the same storagecompartments, thereby alternately cooling the storage compartments eachso that the each of the compartments becomes closer to the settemperature, in a case where the internal temperature of either one ofthe first and the second storage compartments is lower than the settemperature of the storage compartment, performing individual cooling ofonly the other storage compartment, and in a case where the internaltemperatures of both of the storage compartments are lower than therespective set temperatures, stopping the inverter compressor; and acompressor control means for, in a case of alternately cooling the firstand the second storage compartments accompanying with operation of theinverter compressor and, thereafter, switching to the individual coolingof one of the storage compartments having a higher set temperature,decreasing the rotational speed of the inverter compressor.

With the above configurations, in the alternative cooling of the twostorage compartments, refrigerant is supplied by the switching operationof the valve unit alternately to the evaporators. Along with this, whilethe rotational speed of the inverter compressor is increased anddecreased based on the deviations between the set temperatures and theinternal temperatures of each storage compartments. Thus, the storagecompartments are alternately cooled so that the two compartments becomecloser to the respective set temperatures. Here, in the case where theinternal temperature of either one of the storage compartments becomeslower than the set temperature, only the other storage compartment isindividually cooled. In this regard, specifically in the case of beingswitched to the individual cooling of the storage compartment havinghigher set temperature, the rotational speed of the inverter compressoris decreased at the time point where the switching operation isperformed.

Here, when cooling load is higher because of a circumstance such as ahigher ambient temperature, the rotational speed of the invertercompressor tends to be controlled at a higher speed in the alternatecooling and, if this tendency remains when switched to the individualcooling of the storage compartment having higher set temperature,overcooling is concerned.

In this view, in accordance with the present invention, when shifted tothe individual cooling of the storage compartment having higher settemperature, the rotational speed of the inverter compressor isimmediately decreased, i.e. cooling capacity is decreased.

In addition, the configuration may be as follows.

The compressor control means may include a function to decrease therotational speed of the inverter compressor stage by stage atpredetermined time intervals. Though it is more effective to drasticallydecrease the rotational speed of the inverter compressor for decreasingthe cooling capacity. When the rotational speed is drastically decreasedat once, however, motor oil can have trouble circulating inside thecompressor, which may cause an oil shortage. In this view, in thisconfiguration, the rotational speed is decreased stage by stage atpredetermined intervals. Therefore, while the function of decreasing thecooling capacity is ensured, the motor oil can also desirably circulate.

The compressor control means may include a function to decelerate theinverter compressor to a speed not lower than a predetermined minimumrotational speed. With this configuration, in the case where therotational speed of the inverter compressor is decelerated stage bystage, it is decelerated to a speed not lower than the predeterminedminimum rotational speed. The intention is not to overly decrease therotational speed, while contributing to sufficient decreasing of thecooling capacity by slowing to the minimum rotational speed. Thus, in acase of restarting the inverter compressor, cooling capacity can berapidly recovered.

The cooling storage cabinet may include a control stop means for, in acase where a processing instruction to accelerate the invertercompressor is made during the individual cooling of one of the storagecompartments having the higher set temperature, stopping thedeceleration control of the inverter compressor. With thisconfiguration, during the individual cooling of the storage compartmenthaving higher set temperature, in a case where it is determined based ona deviation between the set temperature and the internal temperature tobe undercooling and an instruction to accelerate the inverter compressoris made, the deceleration control of the inverter compressor is stopped.This prevents deficiency in cooling capacity deriving from a overdecrease of the rotational speed of the inverter compressor.

EFFECT OF THE INVENTION

In accordance with the present invention, when shifted to the individualcooling of the storage compartment having higher set temperature, therotational speed of the inverter compressor is immediately decreased,i.e. the cooling capacity is decreased. This results in preventing localovercooling of the storage compartment in, for example, a vicinity of acold air outlet.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view showing a general structure of afreezer-refrigerator of an embodiment in accordance with the presentinvention;

FIG. 2 is a configuration diagram of a freezing cycle and a blockdiagram of a control mechanism portion;

FIG. 3 is a graph showing time-varying change modes of targettemperatures of a freezing compartment and a refrigerating compartment;

FIG. 4 is a table showing a relationship between set speeds and inverterfrequencies of an inverter compressor;

FIG. 5 is a flowchart showing a procedure for controlling a rotationalspeed of the compressor;

FIG. 6 is a graph showing a relationship between time-varying changemodes of internal temperatures and rotational speeds of the compressorin pull-down cooling operation;

FIG. 7 is a flowchart showing a procedure for determining a time ratioof refrigerant supply to the refrigerating compartment and the freezingcompartment;

FIG. 8 is a flowchart showing a procedure for switch cooling controlbetween the refrigerating compartment and the freezing compartment;

FIG. 9 is a flowchart showing cooling operation;

FIG. 10 is a flowchart concerning refrigerating compartment individualovercool preventing control;

FIG. 11 is a timing chart showing changes of the rotational speed of thecompressor and in temperature at each portion;

FIG. 12 is a timing chart showing change of a rotational speed of thecompressor and change of a temperature at each portion of a known art;and

FIG. 13 is a cross-sectional view showing a cold air circulation modeinside a refrigerating compartment of the known art.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

An embodiment in accordance with the present invention will hereinafterbe explained with reference to FIGS. 1 through 11. Illustrated in thisembodiment is a freezer-refrigerator of horizontal type (table type) forcommercial use.

First, a general structure will be explained with reference to FIG. 1.Reference symbol 10 indicates a storage cabinet body, which isconfigured by a horizontally longer heat-insulating box body. Theheat-insulating box body has an opening in front thereof. The storagecabinet body 10 is supported by legs 11. The legs 11 are provided infour corners on a bottom face of the storage cabinet body 10. The insideof the storage cabinet body 10 is separated into right and left sides byan additional heat-insulating partition wall 12. The left and relativelynarrower side is defined as a freezing compartment 13F. The freezingcompartment 13F corresponds to a first storage compartment. The rightand wider side is defined as a refrigerating compartment 13R. Therefrigerating compartment 13R corresponds to a second storagecompartment. Note that each of the freezing compartment 13F and therefrigerating compartment 13R has an opening in the front face thereof.Pivotable heat-insulating doors (not illustrated) are mounted on theopenings so as to be opened and closed.

The left portion of the storage cabinet body 10 viewed from the frontthereof is provided with a machine compartment 14. A heat-insulatingevaporator compartment 15 for the freezing compartment is convexlyformed in the far upper side of the machine compartment 14. Theevaporator compartment 15 is in communication with the freezingcompartment 13F. An evaporator 27F and an internal fan 28F are providedin the evaporator compartment 15. A freezing unit 16 is accommodatedbelow the evaporator compartment 15. The freezing unit 16 can be broughtin and out from the place. A face of the partition wall 12 on therefrigerating compartment 13R side is covered by a duct 17, whereby aevaporator compartment 18 for the refrigerating compartment is formed.An evaporator 27R and an internal fan 28R are provided in the evaporatorcompartment 18.

The freezing unit 16 is configured by placing a compressor 20 and acondenser 21 on a base plate 19. The compressor 20 (that corresponds toan inverter compressor of the present invention) is operated by aninverter motor. The condenser 21 is connected to a refrigerant outletside of the compressor 20. The freezing unit 16 can be brought in andout from the machine compartment 14. In addition, a condenser fan 22(shown only in FIG. 2) is also mounted in the freezing unit 16.

As shown in FIG. 2, an outlet side of the condenser 21 is connected toan inlet 24A of a three-way valve 24 through a drier 23. The three-wayvalve 24 is a valve unit in accordance with the present invention. Thethree-way valve 24 has the single inlet 24A and two outlets 24B, 24C.The outlets 24B, 24C each are connected to first and second refrigerantsupply paths 25F, 25R, respectively. The three-way valve 24 can performa flow path switching operation. In the flow path switching operation,the three-way valve communicatively connects the inlet 24 selectively toeither one of the first and second refrigerant supply paths 25F, 25R.

The first refrigerant supply path 25F is provided with a capillary tube26F for the freezing compartment and the evaporator 27F (a firstevaporator) for the freezing compartment. The capillary tube 26Fcorresponds to a constriction unit. Likewise, the second refrigerantsupply path 25R is provided with a capillary tube 26R for therefrigerating compartment and the evaporator 27R (a second evaporator)for the refrigerating compartment. The capillary tube 26R alsocorresponds to a constriction unit. Refrigerant outlets of the twoevaporators 27F, 27R have a common connection, being connected to anaccumulator 29F, a check valve 30, and an accumulator 29R in that order.The downstream side of the check valve 30 is branched and is connectedto an inlet side of the compressor 20. A refrigerant circulation path 31is thus provided. The circulation path of the refrigerant, which is fromthe outlet side to the inlet side of the compressor 20 as explainedabove, configures a freezing cycle 35. Refrigerant is supplied by thesingle compressor 20 to the two evaporators 27F, 27R through thefreezing cycle 35. In the freezing cycle 35, the supply destination ofliquid refrigerant can be changed by the three-way valve 24.

In this embodiment, refrigerant is supplied alternately to theevaporators 27F, 27R by switch of the three-way valve 24, and therebythe freezing compartment 13F and the refrigerating compartment 13R arealternately cooled. Furthermore, the freezing compartment 13F and therefrigerating compartment 13R each are cooled along predeterminedrespective temperature curves.

The compressor 20 and the three-way valve 24 are controlled by afreezing cycle control circuit 40 containing a CPU therein. The freezingcycle control circuit 40 receives signals from a freezer temperaturesensor 41F (hereinafter referred to as the F-sensor 41F) and arefrigerator temperature sensor 41R (hereinafter referred to as theR-sensor 41R). The F-sensor 41F detects the air temperature in thefreezing compartment 13F. The F-sensor 41F corresponds to a firsttemperature sensor. The R-sensor 41R detects the air temperature in therefrigerating compartment 13R. The R-sensor 41R corresponds to a secondtemperature sensor. The F-sensor 41F and the R-sensor 41R are disposedin a vicinity of an inlet of the freezing compartment evaporatorcompartment 15 and in a vicinity of an inlet of the refrigeratingcompartment evaporator compartment 18, respectively.

On the other hand, a target temperature setting device 45 is provided soas to output various target temperatures in series as time passes. Inthe target temperature setting device 45, the target temperatures ofeach of the freezing compartment 13F and the refrigerating compartment13R are provided as a time-varying change mode (that is, a manner inwhich a target temperature is changed along with a time t). The targettemperature change mode includes two change modes. One of the changemodes is a target temperature change mode in control operation thatcools stored items such as food at a set temperature set by the user.The other mode is a target temperature change mode in operation that isreferred to as pull-down cooling operation that cools down thefreezer-refrigerator that, for example, is first supplied with powerafter installation from a temperature rather higher than the settemperature of the control operation to a temperature zone of thecontrol operation. Each of the change modes are represented by afunction having time t as a variable for each of the freezingcompartment 13F and the refrigerating compartment 13R, and the functionsare stored in a storing means 46 configured by an EEPROM (and the like).For example, functions T_(Fa)=f_(F)(t) and T_(Ra)=f_(R)(t) can beillustrated by a graph shown in FIG. 3. These functions represent changemodes of target temperatures T_(Fa), T_(Ra) of the freezing compartment13F and the refrigerating compartment 13R, respectively, in thepull-down cooling operation.

The two target temperatures T_(Fa), T_(Ra) from the target temperaturesetting device 45 and two internal temperatures T_(F), T_(R) eachobtained from the respective temperature sensors 41F, 41R are providedto a temperature deviation calculating means 47. The temperaturedeviation calculating means 47 then calculates each temperaturedeviation ΔT_(F)=(T_(F)−T_(Fa)) and ΔT_(R)=(T_(R)−T_(Ra)). Then, thevalues of the temperature deviations ΔT_(F), ΔT_(R) each are provided toa temperature deviation integrated value calculating means 48 and aninter-compartment temperature deviation integrating means 50, which areas follows.

In the temperature deviation integrated value calculating means 48, thecontrol is performed to determine the rotational speed of the invertermotor that operates the compressor 20. Note that the set speeds (therotational speeds) of the inverter motor can be switched in seven stagesfrom zeroth speed to sixth. The relationship between the set speeds eachand the inverter frequencies are as shown in FIG. 4.

For example, during a time period of 2 to 10 minutes (5 minutes in thisembodiment), two deviations ΔT_(F), ΔT_(R) are summed and integrated,and the value is provided to a rotational speed control means 49. Therotational speed control means 49 compares the integrated value “A” withpredetermined reference values (a lower limit value and an upper limitvalue). When the integrated value “A” is greater than the upper limitreference value L(A)_UP, the rotational speed of the inverter motor isincreased. When the integrated value “A” is less than the lower limitreference value L(A)_DOWN, the rotational speed of the inverter motor isdecreased. Note that the functions of the temperature deviationintegrated value calculating means 48 and the rotational speed controlmeans 49 are realized by a software executed by the CPU. A processingprocedure of the software is shown with reference to FIG. 5.

That is, upon start of a compressor rotation control routine by the CPU,first, the integrated value A is initialized to, for example, 0 (stepS11). Next, the target temperature setting device 45 reads out thepredetermined functions from the storing means 46, and substitutes avariable t (an elapsed time from the start of this routine) in thefunction, and thereby calculates the target temperatures T_(Ra), T_(Fa)each of the refrigerating compartment 13R and the freezing compartment13F (steps S12, S13), respectively. Then, the deviations ΔT_(R), ΔT_(F)between the target temperatures T_(Ra), T_(Fa) and the actual internaltemperatures T_(R), T_(F) are calculated and integrated (the functionsof the temperature deviation calculating means 47 and the temperaturedeviation integrated value calculating means 48: step S14). Then, theprocess goes to step S15, where the integrated value “A” is comparedwith the upper limit reference value L(A)_UP and the lower limitreference value L (A)_DOWN to increase or decrease the rotational speedof the inverter motor (the function of the rotational speed controlmeans 49: steps S15 to S17).

With such control, suppose, for example, that the time-varying changemodes of the target temperatures T_(Ra), T_(Fa) each of therefrigerating compartment 13R and the freezing compartment 13F are setas dashed-dotted lines in a graph shown FIG. 6, and that the actualinternal temperatures T_(F), T_(R) of the refrigerating compartment 13Rand the freezing compartment 13F are shown by solid lines in the graph.Then, during initial phases after starting the cooling operation, therefrigerating compartment 13R, for example, is cooled so that theinternal temperature T_(R) is still lower than the target temperatureT_(Ra), while the freezing compartment 13F side is cooled so that theinternal temperature T_(F) is substantially equal to the targettemperature T_(Fa). Accordingly, a total temperature deviation goes tominus, and the integrated value “A” also goes to minus. Here, a graph ofthe integrated value “A” shows a saw-tooth appearance because theintegrated value A is initialized at every predetermined time (step S18in FIG. 5). Then, since the integrated value “A” is minus and is lowerthan the lower limit reference value L(A)_DOWN, the inverter frequencyis gradually reduced during the initial phases and, as the result, therotational speed of the compressor 20 is decreased stage by stage, whichdecreases the cooling capacity. Accordingly, the internal temperaturescome closer to the decreasing degrees of the target temperatures.

When the internal temperatures becomes higher than the targettemperatures as the result of decrease in cooling capacity, thetemperature deviations each of the freezing compartment 13F and therefrigerating compartment 13R, as well as the integrated value “A”,shift to plus. When the total integrated value “A” becomes greater thanthe upper limit reference value L (A)_UP, the rotational speed of thecompressor 20 is increased, which causes increase in cooling capacity.Accordingly, the internal temperatures again come close to thedecreasing degrees of the target temperatures. Thereafter, such controlis repeated, and thereby the internal temperatures are decreased inaccordance with the time-varying change modes of the set targettemperatures.

In addition, also in the control operation to cool the stored items suchas food at the set temperatures set by the user, the upper limit valuesand the lower limit values are determined above and under the settemperatures, and the target temperature change modes, which representhow to temporally change the internal temperatures from the upper limitvalues to the lower limit values, are converted into functions andstored in the storing means 46, and in a manner similar to the pull-downcooling operation, the rotational speed of the compressor 20 iscontrolled.

With the above control method, deviations between the targettemperatures read out from the target temperature setting device 45 andthe internal temperatures detected by the sensors 41F, 41R arecalculated and integrated at every predetermined time and, based on thecomparison between the integrated value and the predetermined referencevalues, the rotational speed of the inverter motor that operates thecompressor 20 is changed. Therefore, even if, for example, theheat-insulating doors of the storage cabinet body 10 are temporarilyopened to cause the external air to flow into the compartments, andthereby the internal temperatures have temporarily risen, the rise oftemperatures is rapidly cancelled by closing the heat-insulating doors.Therefore, as far as being observed as the integrated value “A” of thetemperature deviations, there is no rapid change in the integrated value“A”. Consequently, too much sensitive reaction of the freezing cyclecontrol circuit 40, which would cause rapid increase of the rotationalspeed of the compressor 20, does not occur. The control is thereforestabilized.

Furthermore, in this embodiment, refrigerant is supplied by the switchof the three-way valve 24 alternately to the evaporators 27F, 27R toalternately cool the freezing compartment 13F and the refrigeratingcompartment 13R. In addition to this, ratio of refrigerant supply timeto each of the evaporators 27F, 27R in a predetermined time iscontrolled.

As explained above, the values of the temperature deviations ΔT_(F),ΔT_(R) each calculated in the temperature deviation calculating means 47are provided to the inter-compartment temperature deviation integratingmeans 50. The inter-compartment temperature deviation integrating means50 has a function of calculating an “inter-compartment temperaturedeviation” based on the calculated temperature deviations ΔT_(F),ΔT_(R). The “inter-compartment temperature deviation” is a differencebetween the temperature deviations ΔT_(F), ΔT_(R) (ΔT_(F)−ΔT_(R)). The“inter-compartment temperature deviation” is integrated for apredetermined time (for example, for five minutes).

Then, in accordance with the value integrated by the inter-compartmenttemperature deviation integrating means 50, a valve control means 51controls a ratio for opening the first and the second refrigerant supplypaths 25F, 25R. Specifically, the ratio for opening the refrigerantsupply paths 25F, 25R is controlled so that the ratio of R (the secondrefrigerant supply path 25R): F (the first refrigerant supply path 25F)is 3:7 as an initial ratio. Namely, the time rate to cool therefrigerating compartment 13R (a R-compartment individual cooling timerate) is 0.3. The R-compartment individual cooling time rate ischangeable in a range of 0.1 to 0.9 in steps of 0.1. The temperaturedeviation calculating means 47, the inter-compartment temperaturedeviation integrating means 50, and the valve control means 51 areconfigured by software that is executed by the CPU. The specific controlmodes will be explained based on flowcharts shown in FIGS. 7 and 8.

Upon start of a control flow of “R-compartment F-compartment individualcooling time control”, first, an integrated value “B” is initialized(step S21), and the deviation (R-compartment temperature deviation)ΔT_(R) between the actual internal temperature T_(R) of therefrigerating compartment 13R and the target temperature T_(Ra) of therefrigerating compartment 13R is calculated (step S22). Note that theT_(R) is provided from the R-sensor 41R at that time point. Next, thedeviation (F-compartment temperature deviation) ΔT_(F) between theactual internal temperature T_(F) of the freezing compartment 13F andthe target temperature T_(Fa) of the freezing compartment 13F iscalculated (step S23). Note that the T_(F) is also provided from theF-sensor 41F at that time point. Then, the “inter-compartmenttemperature deviation”, which is a difference (ΔT_(R)−ΔT_(F)) betweenthe temperature deviations ΔT_(R), ΔT_(F) of the refrigeratingcompartment 13R and the freezing compartment 13F is calculated. Then,the inter-compartment temperature deviation (ΔT_(F)−ΔT_(R)) isintegrated as the integrated value “B” (step S24). Then, in step S25, itis determined whether or not one cycle, which is set to a predeterminedtime, has elapsed. When the cycle has not elapsed, the steps S22 to S24are repeated until elapse of the cycle to calculate the integrated value“B” of the one cycle.

Next, the integrated value “B” calculated in the step S24 is comparedwith an upper limit reference value L(B)_UP and a lower limit referencevalue L(B)_DOWN (step S26). When the integrated value “B” is greaterthan the upper limit reference value L(B)_UP, it indicates that theintegrated value of the R-compartment temperature deviations ΔT_(R) israther greater, and accordingly, the R-compartment individual coolingtime rate R_(R) is increased by one step (0.1) from the initial value0.3. When the integrated value “B” is less than the lower limitreference value L(B)_DOWN, it indicates that the integrate value of theR-compartment temperature deviation ΔT_(R) is less while theF-compartment temperature deviation ΔT_(F) is rather greater, and,accordingly, the R-compartment individual cooling time rate R_(R) isreduced by one step from the initial value 0.3 (step 28). Then, in stepS29, the integrated value “B” is initialized, and the process returns tothe step S22. Note that, when the integrated value “B” is between theupper limit reference value L(B)_UP and the lower limit reference valueL(B)_DOWN, the process returns to the step S22 without changing theR-compartment individual cooling time rate R_(R).

Upon determination of the R-compartment individual cooling time rateR_(R) as explained above, a control flow of “R-compartment F-compartmentswitch cooling control” shown in FIG. 8 is executed. In this flow chart,first, a value ts of a cycle elapsed time timer is reset (step S31), andthe three-way valve 24 is switched to open the refrigerating compartment13R side (the second refrigerant flow path 25R side) (step S32). Then,it is determined whether or not a cooling time of the refrigeratingcompartment 13R has elapsed (step S33). The steps S32, S33 are repeatedto execute cooling of the refrigerating compartment 13R until elapse ofthe cooling time. Note that the cooling time of the refrigeratingcompartment 13R is calculated by multiplying a predetermined period T₀(e.g. 5 minutes) by the R-compartment individual cooling time rateR_(R).

Then, when the value ts of the cycle elapsed time timer becomes equal toor greater than the value obtained by the multiplication of the periodT₀ by the R-compartment individual cooling time rate R_(R) (T₀*R_(R)),this time, the three-way valve 24 is switched to open the freezingcompartment 13F side (the first refrigerant flow path 25F side) (step34). The step S34 and a step S35 are repeated to execute cooling of thefreezing compartment 13F until elapse of the period T₀. Upon elapse ofthe period T₀, the process returns to the step S31, and the above cycleis repeated. As the result of this, while the one period T₀ of, forexample, 5 minutes is passing, the refrigerating compartment 13R and thefreezing compartment 13F are alternately cooled, with the time rates tocool them being determined by the R-compartment individual cooling timerate R_(R).

Here, in determining the time ratio of refrigerant supply to therefrigerating compartment 13R and the freezing compartment 13F, supposethat control is performed simply to watch the deviations ΔT_(R), ΔT_(F)between the target temperatures and the actual internal temperatures ofthe storage compartments 13R, 13F each and perform longer cooling forthe storage compartment having larger deviation ΔT_(R), ΔT_(F). Then,for example, when the heat-insulating door of one of the storagecompartments is opened to cause the external air to flow into thestorage compartment and thereby the internal temperature is temporarilyincreased. Then, refrigerant supply to the storage compartment isimmediately increased. This would cause progression of cooling in spitethat the door is closed and the internal temperature tends to return,and thus, overcooling of the storage compartment would be a concern. Incontrast, in this embodiment, the difference between the deviationsΔT_(R), ΔT_(F) is obtained and, furthermore, integrated to obtain theintegrated value “B”, based on which the control is performed.Accordingly, even if the internal temperature temporarily rises, sincethere is no rapid change in the integrated value “B” of the temperaturedeviations, unnecessary change of the cooling time rates does notresult. Cooling control is thus stabilized.

Under such an essential control as above, the freezing compartment 13Fand the refrigerating compartment 13R are alternately cooled duringoperation of the compressor 20; in the case where the internaltemperature of either one of the freezing compartment 13F and therefrigerating compartment 13R is lower than the set temperature, onlythe other is cooled; in the case where internal temperatures of both ofthe freezing compartment 13F and the refrigerating compartment 13R arelower than the set temperatures, the compressor 20 is stopped. Thiscontrol will be now explained with reference to a flowchart of FIG. 9.

(Start of Cooling and R-Compartment F-Compartment Alternate Cooling)

Upon start of the compressor 20 (step S41), the three-way valve 24performs flow path switching operation in accordance with the time ratesas determined above, whereby the refrigerating compartment 13R and thefreezing compartment 13F are alternately cooled (step S42). Next, theprocess goes to step S43. In the step S43, the temperature of therefrigerating compartment 13R and a preset refrigerating compartmentlower limit temperature T_(R(OFF)) are compared based on the signal fromthe R-sensor 41R. Furthermore, in step S44, the temperature of thefreezing compartment 13F and a preset freezing compartment lower limittemperature T_(F(OFF)) are compared based on the signal from theF-sensor 41F. In the initial phases of the cooling operation, since theinternal temperature of neither of the compartments has reached thelower limit temperature, the process returns from the step S44 to thestep S42 to perform the R-compartment F-compartment alternate cooling.

(F-Compartment Individual Cooling)

As cooling progresses and when the internal temperature of therefrigerating compartment 13R becomes lower than the presetrefrigerating compartment lower limit temperature T_(R(OFF)), theprocess shifts from the step 43 to step S45. In the step 45, thethree-way valve 24 is switched to a “F-side open state”, whereby onlythe freezing compartment 13F is cooled. Thereafter, the process shiftsto step S46. In the step 46, it is determined based on the signal fromthe R-sensor 41R whether or not the internal temperature of therefrigerating compartment 13R has reached a preset refrigeratingcompartment upper limit temperature T_(R(ON)).

Generally, right after when the R-compartment F-compartment alternatecooling ends, the refrigerating compartment 13R has been sufficientlycooled down. Accordingly, the process goes to the next step S47. In thestep S47, it is determined based on the signal from the F-sensor 41Fwhether or not the internal temperature of the freezing compartment 13Fhas reached the preset freezing compartment lower limit temperatureT_(F(OFF)). The steps S45 to S47 are repeated until when the internaltemperature of the freezing compartment 13F becomes lower than the lowerlimit temperature T_(F(OFF)). As the result of this, only the freezingcompartment 13F is cooled in a concentrated manner.

When the temperature of the refrigerating compartment 13R is raised inthe course of the above cooling operation, the process returns from stepS46 to step S42 to restart the R-compartment F-compartment alternatecooling. That is, since cooling of the refrigerating compartment 13R isalso restarted, the temperature rise of the refrigerating compartment13R can be rapidly depressed.

When the freezing compartment 13F is sufficiently cooled down by the“F-compartment individual cooling” and the internal temperature becomeslower than the freezing compartment lower limit temperature T_(F(OFF)),the process shifts from the step S47 to step S48. In the step S48, thecompressor 20 is stopped. Restart of the compressor 20 is prohibiteduntil elapse of a compressor forced stop time T (step S49). While thecompressor forced stop time T is passing, liquid refrigerant which issupplied to an evaporator 27F in the freezing compartment 13F sideevaporates, whereby the pressure difference between the higher side andthe lower side in the compressor 20 is cancelled.

(Restart of Compressor 20)

Upon elapse of the compressor forced stop time T in the step S49, theprocess goes to step 50. In the step 50, the temperature of the freezingcompartment 13F and a preset freezing compartment upper limittemperature T_(F(ON)) are compared based on the signal from the F-sensor41F. Furthermore, in step S51, the temperature of the refrigeratingcompartment 13R and a preset refrigerating compartment upper limittemperature T_(R(ON)) are compared based on the signal from the R-sensor41R. When the temperature of the freezing compartment 13F or therefrigerating compartment 13R is higher than the upper limit temperaturein either one of the steps, the compressor 20 is started (step S52 orS53). Then, the process shifts to the step S45 or to step S54 to restartcooling of the freezing compartment 13F or the refrigerating compartment13R.

That is, provided that the temperature of either one of the freezingcompartment 13F and the refrigerating compartment 13R becomes higherthan the upper limit temperature, the compressor 20 starts.

(R-Compartment Individual Cooling)

On the other hand, in the case where the R-compartment F-compartmentalternate cooling is being performed, in a case where the freezingcompartment 13F ahead becomes lower than the freezing compartment lowerlimit temperature T_(F(OFF)) (the step S44), the process shifts to stepS54. In the step S54, the three-way valve 24 performs the flow pathswitching operation to a “R-side open state”, whereby only therefrigerating compartment 13R starts to be cooled. Thereafter, theprocess shifts to step S55. In the step S55, it is determined based onthe signal from the F-sensor 41F whether or not the internal temperatureof the freezing compartment 13F has reached the preset freezingcompartment upper limit temperature T_(F(ON)). When the internaltemperature of the freezing compartment 13F has not reached the freezingcompartment upper limit temperature T_(F(ON)), the process goes to thenext step S56. In the step S56, it is determined based on the signalfrom the R-sensor 41R whether the internal temperature of therefrigerating compartment 13R has reached the preset refrigeratingcompartment lower limit temperature T_(R(OFF)). The “R-compartmentindividual cooling” is executed until when the internal temperature ofthe refrigerating compartment 13R reaches the preset refrigeratingcompartment lower limit temperature T_(R(OFF)).

Note that, when the temperature of the freezing compartment 13F hasrisen in the course of the control operation, the process returns fromthe step S55 to the step S42 to restart the R-compartment F-compartmentalternate cooling.

When the temperature of the refrigerating compartment 13R is cooled downto the refrigerating compartment lower limit temperature T_(R(OFF)) asthe result of the “R-compartment individual cooling” (step S56),according to the prior art, both of the F- and R-compartments would beregarded to have been cooled down, and the compressor 20 would bestopped. In this embodiment in accordance with the present invention,the process again shifts to the “F-compartment individual cooling” (thestep S45), whereby the temperature of the freezing compartment 13F iscooled down to the freezing compartment lower limit temperatureT_(F(OFF)) and, thereafter, the compressor 20 is stopped (the step S48).

Therefore, regardless of which one of the freezing compartment 13F andthe refrigerating compartment 13R reaches the lower limit temperaturefirst, the process is bound to the eventual cooling of the freezingcompartment 13F to cool down its temperature to the lower limittemperature T_(F(OFF)). This forestalls rise of the temperature of thefreezing compartment 13F to an improper zone during the subsequent stopperiod of the compressor 20.

Now, in this embodiment, a R-individual overcool preventing means isprovided. The R-individual overcool preventing means preventsovercooling of the R-compartment, i.e. the refrigerating compartment13R, specifically in the case of switching from the R-compartmentF-compartment alternate cooling to the F-compartment individual cooling.In this means, control as shown in a flowchart of FIG. 10 is performed.The control is executed separately from the control shown in theflowchart of FIG. 9.

First, in step S61, a deceleration interval timer is reset. Thereafter,in step S62, it is determined whether start of “R-individual overcoolpreventing control” is requested (including the executed state) or stopof the control is requested (including the stopped state). In the casewhere the start is requested (in a case where a flag is ON), the processshifts to step S63.

In the step S63, the set speed of the compressor 20 at that time point(see FIG. 4) is detected and, when the set speed exceeds the “2ndspeed”, the process shifts to step S64. In this step, a measured time bythe deceleration interval timer is detected, and the steps S62 to thesteps S64 are repeated until when “30 seconds” elapses as thedeceleration interval. When “30 seconds” has elapsed as the decelerationinterval in the step S64, the rotational speed of the compressor 20 isdecreased by one stage (step S65) and, thereafter, the process returnsto the step S61. The operation as above is repeated as long as the flagis ON.

In the case where stop of the “R-individual overcool preventing control”is requested (in a case where the flag is OFF) in the course of therepeated operation, the process returns to the step S61 to stop thedeceleration control of the compressor 20.

Furthermore, also in the case where it is determined in the step S63that the set speed of the compressor 20 has been decelerated to the “2ndspeed”, the process returns to the step S61 to stop further decelerationcontrol of the compressor 20.

Referring to the cooling operation shown in the flowchart of FIG. 9 asexplained above, at the time point where the process shifts from theR-compartment F-compartment alternate cooling to the R-compartmentindividual cooling, i.e. during when the process shifts from the stepS44 to the step S54, the request for start of the “R-individual overcoolpreventing control” is made (the flag is turned ON: step S70) and,subsequently, the rotational speed of the compressor 20 is decreased byone stage (step S71).

Note that at the time point where the process returns from theR-compartment individual cooling to the R-compartment F-compartmentalternate cooling, i.e. during when the process shifts from the step S55to the step S42, the request for stop of the “R-individual overcoolpreventing control” is made (the flag is turned OFF: step S72).Likewise, also in the case where the process shifts from theR-compartment individual cooling to the F-compartment individualcooling, i.e. in the case where the process shifts from the step S56 tothe step S45, the request for stop of the “R-individual overcoolpreventing control” is made (the flag is turned OFF: step S73).

Furthermore, in the R-compartment individual cooling, in performing thecompressor rotation control shown in the flowchart of FIG. 5 to coolalong the predetermined temperature curves, in the case where it isdetermined to be undercooling and an instruction to accelerate theinverter compressor is made (step S16), the request for stop of the“R-individual overcool preventing control” is likewise made (the flag isturned OFF: step S74) before the process shifts to the step S18.

Next, control mainly of the case of shifting from the R-compartmentF-compartment alternate cooling to the R-compartment individual coolingwill be explained with reference to a timing chart of FIG. 11.

In the R-compartment F-compartment alternate cooling, the three-wayvalve 24 performs the flow path switching operation in accordance withthe time ratio determined as above and, along with this, the rotationalspeed of the compressor 20 is controlled to follow the targettemperature curves, thereby alternatively cooling the refrigeratingcompartment 13R and the freezing compartment 13F. Here, when coolingload is higher because of a circumstance such as a higher ambienttemperature, the rotational speed tends to be controlled at a higherspeed.

In such a state and when the internal temperature of the freezingcompartment 13F becomes lower than the lower limit temperatureT_(F(OFF)), the request for start of the “R-individual overcoolpreventing control” is made (S70 in FIG. 9), and the rotational speed ofthe compressor 20 is decreased by one stage (step S71 in the samefigure) and, subsequently, the three-way valve 24 performs the flowpathswitching operation to the “R-side open state”. Thus, only therefrigerating compartment 13R is cooled (the R-compartment individualcooling: step S54 in the same figure).

During execution of the R-compartment individual cooling, the rotationalspeed of the compressor 20 is decreased by one stages at every 30seconds elapsed from the start. Then, when the refrigerating compartment13R becomes lower than the lower limit temperature T_(R(OFF)), therequest for stop of the “R-individual overcool preventing control” ismade (the step S73 in FIG. 9) and, subsequently, the process shifts tothe F-compartment individual cooling (the step S45 in the same figure).Thereafter, when the internal temperature of the freezing compartment13F again becomes lower than the lower limit temperature T_(F(OFF)), thecompressor 20 is stopped (the step S48 in the same figure).

Note that, during when the rotational speed of the compressor 20 isdecreased stage by stage, it is decreased to a speed not lower than the“2nd speed” (40 Hz). In addition, when the instruction to accelerate thecompressor 20 is made during the R-compartment individual cooling, the“R-individual overcool preventing control” is stopped.

Thus, in this embodiment, when shifted to the R-compartment individualcooling, the rotational speed of the compressor 20 is drasticallydecreased in a short time, i.e. the cooling capacity is drasticallydecreased. Therefore, the manner of decrease in temperature (atemperature curve Y shown by dashed line in FIG. 11) at a point in frontof the cold air outlet where the temperature is the lowest in therefrigerating compartment 13R, i.e. at a point 61 above an uppermost netlack 60, is also reduced at the same degree with the manner of decreasein temperature (a temperature curve X shown by solid line in the samefigure) in the vicinity of the internal air inlet where the R-sensor 41Ris located. As the result of this, generation of an overcooled localzone is prevented.

Note that, if the rotational speed of the compressor 20 is drasticallydecreased at once (for example, from 76 Hz to 40 Hz), motor oil can havetrouble circulating inside the compressor, which may cause an oilshortage. In this embodiment, the rotational speed is decreased stage bystage at every 30 seconds. Therefore, the motor oil can also desirablycirculate.

Furthermore, the compressor 20 is decelerated not lower than thepredetermined minimum speed (“the second speed”). The intention here isnot to over-decrease the rotational speed for the case of restarting thecompressor 20, while contributing to sufficient reduction of the coolingcapacity by decelerating to the “second speed”.

Furthermore, in the case where the instruction to accelerate thecompressor 20 is made in the R-compartment individual cooling, “theR-individual overcool preventing control” is stopped. Therefore,likewise, there is no concern of causing deficiency in cooling capacityderiving from over decrease of the rotational speed of the invertercompressor.

Note that the present invention is not limited to the embodimentexplained as above with reference to the drawings. For example, thefollowing embodiments are also included in the scope of the presentinvention.

(1) The time interval in the case of decreasing the rotational speed ofthe inverter compressor stage by stage is not limited to the “30seconds” described in the above embodiment. It may be any other timeinterval, considering the number of stages, the inverter frequencies inthe stages each, the capacity of the compressor, and the like.(2) In determining the time ratio of refrigerant supply to therefrigerating compartment and the freezing compartment, it is notlimited to be based on the integrated value of the deviations betweenthe target temperatures and the actual internal temperatures of thestorage compartments each as described in the above embodiment. It maybe based on only the deviations. Furthermore, the time ratio ofrefrigerant supply may be fixed.(3) In the case illustrated in the above embodiment, when cooling thestorage compartments each along the predetermined temperature curves,the rotational speed of the inverter compressor is controlled based onthe integrated value of the deviations between the target temperaturesand the actual internal temperatures to maintain the storagecompartments at the target temperatures. The rotational speed of theinverter compressor may be controlled based on only the deviations.(4) In the above embodiment, when the internal temperatures of both ofthe storage compartments become lower than the set temperatures and theinverter compressor is stopped, the freezing compartment is bound to beeventually cooled. The control method may be such that the invertercompressor is stopped when the internal temperatures of both of thestorage compartments become lower than the set temperatures regardlessof which one is eventually cooled.(5) In the above embodiment, the freezer-refrigerator having thefreezing compartment and the refrigerating compartment is illustrated.The present invention is not limited to this. The cooling storagecabinet may be a one having a refrigerating compartment and a thawingcompartment, two refrigerating compartments or two freezing compartmentsthat differ from each other in storing temperature, or the like. Theessential point is that the cooling storage cabinet has storage cabinetswhich set temperatures differ from each other, and that refrigerant issupplied from a shared compressor to evaporators each provided in therespective storage cabinets. The present invention may be appliedbroadly and all-round to such cooling storage cabinets.

1-5. (canceled)
 6. A method of operating a cooling storage cabinet, themethod comprising: providing an inverter compressor, a condenser, avalve unit, a first and a second evaporator, constriction unitsconfigured to constrict refrigerant flowing into each of theevaporators, and a first and a second storage compartments, the firstand the second storage compartments having set temperatures differingfrom each other, the first and the second storage compartments havingthe first and the second evaporators; supplying the refrigerant by thevalve unit alternately to the evaporators, while changing a rotationalspeed of the inverter compressor based on deviations between the settemperatures of each storage compartment and internal temperatures ofthe same storage compartments, thereby alternately cooling each storagecompartment each so that the each compartment becomes closer to the settemperature; performing individual cooling of only the other storagecompartment when the internal temperature of either one of the first andthe second storage compartment is lower than the set temperature, andstopping the inverter compressor when the internal temperatures of bothof the storage compartments are lower than the respective settemperatures; and alternately cooling the first and the second storagecompartments with operation of the inverter compressor and, thereafter,switching to the individual cooling of the storage compartment having ahigher set temperature, decreasing the rotational speed of the invertercompressor.
 7. A cooling storage cabinet, comprising: a freezing cycle,including an inverter compressor configured to have a changeablerotational speed, a condenser configured to dissipate heat fromrefrigerant compressed by the inverter compressor, a valve unit havingan inlet and two outlets, the inlet being connected to the condenserside, the two outlets being connected to a first and a secondrefrigerant supply paths, the valve unit being configured to switch aflow path between the inlet side and selectively with at least one ofthe first and the second refrigerant supply paths, a first and a secondevaporator, each of the first and the second evaporator being configuredto be provided in respective one of the first and the second refrigerantsupply paths, constriction units, each of the constriction units beingconfigured to constrict refrigerant flowing into one of the evaporators,and a refrigerant circulation path configured to provide a commonconnection between refrigerant outlet sides of the first and the secondevaporators, the refrigerant circulation path being configured to beconnected to an refrigerant inlet side of the inverter compressor; astorage cabinet body having a first and a second storage compartments,the first and the second storage compartments being configured to haveset temperatures differing from each other and to be cooled by cold airgenerated by the first and the second evaporators; a first and a secondtemperature sensors, each of the first and the second temperaturesensors being configured to detect internal temperature of respectiveone of the first and the second storage compartments; and an operationcontrol means for, during operation of the inverter compressor,supplying the refrigerant by the valve unit alternately to theevaporators, while changing a rotational speed of the invertercompressor based on deviations between the set temperatures of thestorage compartments each and internal temperatures of the same storagecompartments, thereby alternately cooling the storage compartments eachso that the each of the compartments becomes closer to the settemperature, in a case where the internal temperature of either one ofthe first and the second storage compartments is lower than the settemperature of the storage compartment, performing individual cooling ofonly the other storage compartment, and in a case where the internaltemperatures of both of the storage compartments are lower than therespective set temperatures, stopping the inverter compressor; and acompressor control means for, in a case of alternately cooling the firstand the second storage compartments accompanying with operation of theinverter compressor and, thereafter, switching to the individual coolingof one of the storage compartments having a higher set temperature,decreasing the rotational speed of the inverter compressor.
 8. Thecooling storage cabinet according to claim 7, wherein the compressorcontrol means includes a function to decrease the rotational speed ofthe inverter compressor stage by stage at predetermined time intervals.9. The cooling storage cabinet according to claim 8, wherein thecompressor control means includes a function to decelerate the invertercompressor to a speed not lower than a predetermined minimum rotationalspeed.
 10. The cooling storage cabinet according to claim 8, comprisinga control stop means for, in a case where a processing instruction toaccelerate the inverter compressor is made during the individual coolingof one of the storage compartments having the higher set temperature,stopping the deceleration function of the inverter compressor.
 11. Thecooling storage cabinet according to claim 9, comprising a control stopmeans for, in a case where a processing instruction to accelerate theinverter compressor is made during the individual cooling of one of thestorage compartments having the higher set temperature, stopping thedeceleration function of the inverter compressor.